Function from_bytes_auto 

pub fn from_bytes_auto<'a, T>(b: &'a [u8]) -> DeResult<T>
where
    T: Deserialize<'a>,

The same as from_bytes but deserialize_any will deserialize byte string as str if input bytes are valid UTF-8, otherwise as bytes.

Note

Thus making impossible to deserialize advanced Serde constructs like tagged enums with some penalty for simpler use cases.